diff --git a/src/features/encoders/jxl/worker/jxlEncode.ts b/src/features/encoders/jxl/worker/jxlEncode.ts
index 0378c2a7..40d71680 100644
--- a/src/features/encoders/jxl/worker/jxlEncode.ts
+++ b/src/features/encoders/jxl/worker/jxlEncode.ts
@@ -14,28 +14,17 @@ import type { JXLModule } from 'codecs/jxl/enc/jxl_enc';
 import type { EncodeOptions } from '../shared/meta';
 
 import { initEmscriptenModule } from 'features/worker-utils';
-import { threads, simd } from 'wasm-feature-detect';
+import { threads } from 'wasm-feature-detect';
 
 import wasmUrl from 'url:codecs/jxl/enc/jxl_enc.wasm';
 
 import wasmUrlWithMT from 'url:codecs/jxl/enc/jxl_enc_mt.wasm';
 import workerUrl from 'omt:codecs/jxl/enc/jxl_enc_mt.worker.js';
 
-import wasmUrlWithMTAndSIMD from 'url:codecs/jxl/enc/jxl_enc_mt_simd.wasm';
-import workerUrlWithSIMD from 'omt:codecs/jxl/enc/jxl_enc_mt_simd.worker.js';
-
 let emscriptenModule: Promise<JXLModule>;
 
 async function init() {
   if (await threads()) {
-    if (await simd()) {
-      const jxlEncoder = await import('codecs/jxl/enc/jxl_enc_mt_simd');
-      return initEmscriptenModule(
-        jxlEncoder.default,
-        wasmUrlWithMTAndSIMD,
-        workerUrlWithSIMD,
-      );
-    }
     const jxlEncoder = await import('codecs/jxl/enc/jxl_enc_mt');
     return initEmscriptenModule(jxlEncoder.default, wasmUrlWithMT, workerUrl);
   }
diff --git a/src/features/encoders/webP/worker/webpEncode.ts b/src/features/encoders/webP/worker/webpEncode.ts
index 035c166d..1b026dd9 100644
--- a/src/features/encoders/webP/worker/webpEncode.ts
+++ b/src/features/encoders/webP/worker/webpEncode.ts
@@ -14,18 +14,12 @@ import type { WebPModule } from 'codecs/webp/enc/webp_enc';
 import type { EncodeOptions } from '../shared/meta';
 
 import { initEmscriptenModule } from 'features/worker-utils';
-import { simd } from 'wasm-feature-detect';
 
 import wasmUrl from 'url:codecs/webp/enc/webp_enc.wasm';
-import wasmUrlWithSIMD from 'url:codecs/webp/enc/webp_enc_simd.wasm';
 
 let emscriptenModule: Promise<WebPModule>;
 
 async function init() {
-  if (await simd()) {
-    const webpEncoder = await import('codecs/webp/enc/webp_enc_simd');
-    return initEmscriptenModule(webpEncoder.default, wasmUrlWithSIMD);
-  }
   const webpEncoder = await import('codecs/webp/enc/webp_enc');
   return initEmscriptenModule(webpEncoder.default, wasmUrl);
 }
diff --git a/src/features/encoders/wp2/worker/wp2Encode.ts b/src/features/encoders/wp2/worker/wp2Encode.ts
index 1c12573b..f59478b1 100644
--- a/src/features/encoders/wp2/worker/wp2Encode.ts
+++ b/src/features/encoders/wp2/worker/wp2Encode.ts
@@ -14,28 +14,17 @@ import type { WP2Module } from 'codecs/wp2/enc/wp2_enc';
 import type { EncodeOptions } from '../shared/meta';
 
 import { initEmscriptenModule } from 'features/worker-utils';
-import { threads, simd } from 'wasm-feature-detect';
+import { threads } from 'wasm-feature-detect';
 
 import wasmUrl from 'url:codecs/wp2/enc/wp2_enc.wasm';
 
 import wasmUrlWithMT from 'url:codecs/wp2/enc/wp2_enc_mt.wasm';
 import workerUrl from 'omt:codecs/wp2/enc/wp2_enc_mt.worker.js';
 
-import wasmUrlWithMTAndSIMD from 'url:codecs/wp2/enc/wp2_enc_mt_simd.wasm';
-import workerUrlWithSIMD from 'omt:codecs/wp2/enc/wp2_enc_mt_simd.worker.js';
-
 let emscriptenModule: Promise<WP2Module>;
 
 async function init() {
   if (await threads()) {
-    if (await simd()) {
-      const wp2Encoder = await import('codecs/wp2/enc/wp2_enc_mt_simd');
-      return initEmscriptenModule(
-        wp2Encoder.default,
-        wasmUrlWithMTAndSIMD,
-        workerUrlWithSIMD,
-      );
-    }
     const wp2Encoder = await import('codecs/wp2/enc/wp2_enc_mt');
     return initEmscriptenModule(wp2Encoder.default, wasmUrlWithMT, workerUrl);
   }
diff --git a/src/sw/to-cache.ts b/src/sw/to-cache.ts
index cbc922f5..dace22e2 100644
--- a/src/sw/to-cache.ts
+++ b/src/sw/to-cache.ts
@@ -1,4 +1,4 @@
-import { threads, simd } from 'wasm-feature-detect';
+import { threads } from 'wasm-feature-detect';
 import webpDataUrl from 'data-url:./tiny.webp';
 import avifDataUrl from 'data-url:./tiny.avif';
 
@@ -75,9 +75,6 @@ import avifEncWasm from 'url:codecs/avif/enc/avif_enc.wasm';
 import * as avifEnc from 'entry-data:codecs/avif/enc/avif_enc.js';
 
 // JXL
-import * as jxlEncMtSimdWorker from 'entry-data:codecs/jxl/enc/jxl_enc_mt_simd.worker.js';
-import * as jxlEncMtSimd from 'entry-data:codecs/jxl/enc/jxl_enc_mt_simd';
-import jxlEncMtSimdWasm from 'url:codecs/jxl/enc/jxl_enc_mt_simd.wasm';
 import * as jxlEncMtWorker from 'entry-data:codecs/jxl/enc/jxl_enc_mt.worker.js';
 import * as jxlEncMt from 'entry-data:codecs/jxl/enc/jxl_enc_mt';
 import jxlEncMtWasm from 'url:codecs/jxl/enc/jxl_enc_mt.wasm';
@@ -89,15 +86,10 @@ import oxiMtWasm from 'url:codecs/oxipng/pkg-parallel/squoosh_oxipng_bg.wasm';
 import oxiWasm from 'url:codecs/oxipng/pkg/squoosh_oxipng_bg.wasm';
 
 // WebP
-import * as webpEncSimd from 'entry-data:codecs/webp/enc/webp_enc_simd';
-import webpEncSimdWasm from 'url:codecs/webp/enc/webp_enc_simd.wasm';
 import * as webpEnc from 'entry-data:codecs/webp/enc/webp_enc';
 import webpEncWasm from 'url:codecs/webp/enc/webp_enc.wasm';
 
 // WP2
-import * as wp2EncMtSimdWorker from 'entry-data:codecs/wp2/enc/wp2_enc_mt_simd.worker.js';
-import * as wp2EncMtSimd from 'entry-data:codecs/wp2/enc/wp2_enc_mt_simd';
-import wp2EncMtSimdWasm from 'url:codecs/wp2/enc/wp2_enc_mt_simd.wasm';
 import * as wp2EncMtWorker from 'entry-data:codecs/wp2/enc/wp2_enc_mt.worker.js';
 import * as wp2EncMt from 'entry-data:codecs/wp2/enc/wp2_enc_mt';
 import wp2EncMtWasm from 'url:codecs/wp2/enc/wp2_enc_mt.wasm';
@@ -105,14 +97,8 @@ import * as wp2Enc from 'entry-data:codecs/wp2/enc/wp2_enc';
 import wp2EncWasm from 'url:codecs/wp2/enc/wp2_enc.wasm';
 
 export const theRest = (async () => {
-  const [
-    supportsThreads,
-    supportsSimd,
-    supportsWebP,
-    supportsAvif,
-  ] = await Promise.all([
+  const [supportsThreads, supportsWebP, supportsAvif] = await Promise.all([
     threads(),
-    simd(),
     ...[webpDataUrl, avifDataUrl].map(async (dataUrl) => {
       if (!self.createImageBitmap) return false;
       const response = await fetch(dataUrl);
@@ -153,15 +139,7 @@ export const theRest = (async () => {
   }
 
   // JXL
-  if (supportsThreads && supportsSimd) {
-    items.push(
-      jxlEncMtSimdWorker.main,
-      ...jxlEncMtSimdWorker.deps,
-      jxlEncMtSimd.main,
-      ...jxlEncMtSimd.deps,
-      jxlEncMtSimdWasm,
-    );
-  } else if (supportsThreads) {
+  if (supportsThreads) {
     items.push(
       jxlEncMtWorker.main,
       ...jxlEncMtWorker.deps,
@@ -181,22 +159,10 @@ export const theRest = (async () => {
   }
 
   // WebP
-  if (supportsSimd) {
-    items.push(webpEncSimd.main, ...webpEncSimd.deps, webpEncSimdWasm);
-  } else {
-    items.push(webpEnc.main, ...webpEnc.deps, webpEncWasm);
-  }
+  items.push(webpEnc.main, ...webpEnc.deps, webpEncWasm);
 
   // WP2
-  if (supportsThreads && supportsSimd) {
-    items.push(
-      wp2EncMtSimdWorker.main,
-      ...wp2EncMtSimdWorker.deps,
-      wp2EncMtSimd.main,
-      ...wp2EncMtSimd.deps,
-      wp2EncMtSimdWasm,
-    );
-  } else if (supportsThreads) {
+  if (supportsThreads) {
     items.push(
       wp2EncMtWorker.main,
       ...wp2EncMtWorker.deps,